Growth Mechanisms of Carbon Onions Obtained by Thermal Treatment

2 Growth Mechanisms of Carbon Onions Obtained by Thermal Treatment 

A thermal treatment of different carbon forms can lead to the formation of onionlike species as well. As for diamond particles, their surface structure plays an important role for the actual outcome of the process. If it is covered with functional groups, the bonding sites are saturated which renders a graphitization more difficult From danghng bonds, on the other hand, graphitized domains will arise that can serve as nucleation center to the formation of carbon onions. In this process, a suitable orientation of lattice planes as well as a small particle size that 

Altogether it is reasonable to assume that different mechanisms, and predominantly among them a spiral and a shell-wise growth, proceed in parallel, regardless of starting material and method of preparation. 

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